Go read the research yourself, it's well validated and peer reviewed. The stat's is as sound as you are going to get and if you bother to dig a bit you will see that the results largely stay the same no mater how they try to debunk it.

You might notice that on the Left side of the table, countries have a tendency to be more stable and on the right side the opposite is true.

The breeding of let's say less " savvy individuals are a world phenomena at the moment, Europe and the US is suffering the same plight , largely thanks to low professional population growth rates and high immigration of Low " savvy individuals , especially illegal immigrants from the middle east and Africa The social safety net is also doing a lot of Apbreastude damage to the population.

On the up side officially they are encouraging the immigration of High IQ individual from all over the world, including India India is not a attractive immigration destination, consequently the cream of the crop is leaving

Now China on the other hand is a definite threat since the ave IQ is high by comparison to the rest of the world. In all areas they can be considered to be a potential treat

On Muslims having higher birth rates , I have no clue. But If that is the case non Muslims might have to consider immigrating ( My golly they are becoming a pestilence )